chore: import upstream snapshot with attribution

paddle/phi/kernels/cpu/where_kernel.cc

@@ -0,0 +1,54 @@
+// Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "paddle/phi/kernels/where_kernel.h"
+
+#include "paddle/phi/core/kernel_registry.h"
+
+namespace phi {
+
+template <typename T, typename Context>
+void WhereKernel(const Context& dev_ctx,
+                 const DenseTensor& condition,
+                 const DenseTensor& x,
+                 const DenseTensor& y,
+                 DenseTensor* out) {
+  const bool* cond_data = condition.data<bool>();
+  const T* x_data = x.data<T>();
+  const T* y_data = y.data<T>();
+  auto x_numel = x.numel();
+
+  T* out_data = dev_ctx.template Alloc<T>(out);
+  if (out && out->numel() == 0) {
+    return;
+  }
+
+  for (int i = 0; i < x_numel; i++) {
+    out_data[i] = cond_data[i] ? x_data[i] : y_data[i];
+  }
+}
+
+}  // namespace phi
+
+PD_REGISTER_KERNEL(where,
+                   CPU,
+                   ALL_LAYOUT,
+                   phi::WhereKernel,
+                   float,
+                   double,
+                   int,
+                   int64_t,
+                   bool,
+                   phi::complex64,
+                   phi::complex128) {}